Train-annunciating apparatus



Nov. 11, 1930. P. H. CRAGO 1,781,497

TRAIN ANNUNQIATING APPARATUS Filed Sept. 20, 1929 I INVENTORI P H CIQ a 0 Patented Nov. 11, 1930 A UNITED STATES PATENT OFFICE PAUL H. CRAGO, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, or SYLVANIA SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENN- TRAIN-ANNUNCIATING APPARATUS Application filed September 20, 1929. Serial No. 393,926.

My invention relates to train annunciating apparatus, thatis, to apparatus for announcing or indicating the approach of trains in an interlocking tower or other central location.

One vision of novel and improved means for limiting the time of operation of the annunciator.

I will describe one form of apparatus embodying my invention, and'will then point of a railway track, which rails are divided by Y insulated joints 2 to form a track section EF. This section is provided with a track circuit comprising a track battery 3, and a track relay T This track relay includes a back contact 6, which contact is therefore normally open and becomes closed when the section E-F is'occupied by a train.

Located in an interlocking tower or other central point, is anannunciator A, which, as here shown, is an electric'bell. This bell is controlled by a slow pick-up relay G, and b a cut-out relay R. As here shown, the relay is a thermal relay having an operating winding 4 and a normally open contact 8 which becomes closed after winding 4 has been energized for a given interval of time.

'Normally, track relay T is energized, so that back contact 6 of this relay is open, with the result that the bell A and the relaysG and R are all de-energized. When a train enters section EF, it will de-energize relay T so that back contact 6 of this relay will become closed. A circuit will then be closed from terminal B of a suitable source of current through back contact 6, back point of contact 7 of relay R, bell A and winding 4 of relay G in multiple, to terminal 0 of the same source of current. Bell A will then begin to ring, and after a given interval of time contact 8 of relay G will close, thereby closing a pick-up circuit for relay R, which circuit passesfrom terminal B, through back contact 6, contact 8 of relay G, and the windfeature of my invention is the pro ing of relay R to terminal 0. The energizet1on of relay R will cause the back point of contact 7 of this relay to become opened, thereby opening the circuit for bell A and the operating windlng of relay G, with the result that bell A will cease to ring. Relay R will then remain energized as long as relay T is energized, because of a stick circuit which passes from terminal B, through back contact 6, front point of contact 7 of relay R, and the winding of this relay to terminal 0. As soon as the train asses out of section E-F, track relay T Wlll again become energized, and this will open the stick circuit for relay B, so that the parts'will be restored to the conditions in which they are shown in the drawing.

It will be seen from the foregoing, that bell A will ring for only a limited interval of time after a train enters section EF.

One important feature of my invention is that no current is consumed by the annunciating apparatus, except when section E--F is occupied by a train. Another feature is that the thermal relay G is energized only during the limited interval of time in which the bell A is in operation.

Although as shown in the drawing the winding 4 of relay G is connected in multiple 1 with the bell A, this specific arrangement of the circuit is not essential, because this winding might equally well be placed in series with the bell. I

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. A system for indicating of trains, comprising a section of. track, a train controlled relay associated with said section and having a normally open contact which is closed when the section is occupied, an annunciator, a slow pick-up relay, a normally de-energized cut-out relay, a circuit for. said annunciator including said normalthe approach I cut-out relay inc u ly dpen contact and a baclz contact of said cut-out relay as well as the winding of said slow pick-up rela a pick-u circuit for said sai normally open contact and the contact of said slow pick-up relay, and a stick circuit for said cut-out relay including said normally open contact and a front contact of the cut-out relay. 7

2. A system for indicating the approach of trains, comsrising a section of track, a 7

train controlle relay associated with said section and having a normally open contact which is closed when the section is occupied, i

an annunciator, a slow pick-up relay, means for simultaneousl setting said annunciator into operation an energizing said slow pickup relay in response to the closing of said contact, a normally de-energized cut-out relay, means for energizing said cut-out relay when said slow pick-up relay closes and for subsequently keeping it energized as long as said normally open contact is closed, and means for stopping the operation of said annunciator and de-energizing said slow pickup relay when said cut-out relay closes.

In testimony whereof I afiix my signature.

. PAUL H. CRAGO. 

